We propose here to test the hypothesis that a computer programmed to interact in dialogue can provide direct, economical assistance to patients with important, common medical problems -- problems including urinary tract infections, headache, hypertension, diabetes and hyperlipoproteinemia that require individualized attention too complex for library materials such as pamphlets and books -- problems that tradionally require professional help but for which professional help is sometimes unavailable and always expensive. For the proposed study we have chosen hyperlipoproteinemia, types II and IV. Patients will be interviewed by computer for information of relevance to their particular difficulties. The computer will then, over a series of sessions, provide advice, strategies and instruction regarding therapeutic, dietary behavior. The patients will be in control of the process at all times, the specifics of treatment being determined by them in consultation with the computer.